In recent years, in view of the fact that light emission with a high brightness is obtainable through low-voltage driving, an organic electroluminescence device (hereinafter also referred to as “device” or “organic EL device”) has been actively researched and developed. In general, the organic electroluminescence device is constituted of an organic layer including a light emitting layer and a pair of electrodes interposing this light emitting layer therebetween, and energy of an exciton generated through recombination of an electron injected from a cathode and a hole injected from an anode is utilized for the light emission.
In recent years, an improvement of efficiency of the device is being advanced by using a phosphorescent material. For example, an organic electroluminescence device having enhanced luminous efficiency and device durability is researched by using an iridium complex, a platinum complex or the like as the phosphorescent material.
Also, a dope-type device using a light emitting layer having a light emitting material doped in a host material is widely employed.
US-A-2008/297033 and JP-A-2008-311607 disclose iridium complexes containing a condensed ring azole ligand, having high durability and capable of achieving blue light emission.